Yeah I think this is quite a common experience for T1 diabetics sadly

I remember having a sleepover when I was like 11 at my friend's house, and her step-dad was also T1 and said I wasn't allowed to have hot chocolate before sleeping and was really mean about it. That's really stuck with me for some reason

As others have said, how we manage our diabetes is quite personal and it's not ever productive to tell someone how to regulate their own. There is also a fine line between that and giving some "well-meaning" advice, which I think some people fail to do. It's whatever works best for you.
Saying that
@gail2 I've heard a few stories of people who are almost obsessive about their diabetes, checking their sugars constantly and not eating carbs at all out of fear of sugar level spikes. That's when I would perhaps want to intervene and give them some advice, as at that point it's affecting their wellbeing

but I think the choice of words ("you worry too much") in this case is a bit unnecessary. It sounds what you're doing is perfectly fine, and works for you. If this person is close to you, it may be worth sitting down with them and having a conversation about the language you use with each other around diabetes and how their words upset you. I've had similar conversations with partners in the past and it's been really helpful. People don't realise the impact of their words sometimes.